JP2000263218A - Method and body for ultrasonic cast-in - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the thermal effect, to increase the bonding strength, and to achieve the complicated and fine bonding by continuously or intermittently applying the ultrasonic wave to a work to be bonded arranged in a mold when a poured second work to be bonded is in a semi-solidified condition. SOLUTION: A solid 5 of a first work to be bonded is inserted in a die 7. A molten metal 6 of a second work to be bonded of a separately molten aluminum alloy, etc., is poured into the die 7. In a solidifying process in which the molten metal 6 of the second work is in a semi-solidified condition, the ultrasonic vibration is continuously or intermittently applied to the solid 5 of the first work by a pressing plate. The ultrasonic vibration is of, for example, 18 KHz and 500 W. After the molten metal 6 of the second work is completely solidified, a vibrating body 3 is detached to complete the bonding. By applying the ultrasonic wave, the shear strength of at least two times that of the ultrasonic cast-in bonding in the liquid condition can be obtained. The cast-in bonding is possible even when the first work is a round bar, and its bonding surface forms an acute angle in the direction of the ultrasonic vibration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention places a to-be-molded member (hereinafter, referred to as a first object) in a mold and pours cast metal (hereinafter, referred to as a second object). TECHNICAL FIELD The present invention relates to an ultrasonic cast-in joining method and an ultrasonic cast-in joint in which ultrasonic vibration is applied to form a joint having an integral joint.

[0002]

2. Description of the Related Art Conventionally, when a metal part as a first workpiece and a casting (cast metal) as a second workpiece are cast-joined to each other, the first workpiece and the second workpiece are connected to each other. A joining method of joining by a frictional force or a thermal expansion force is used. In this method, since the joint is a mechanical contact and a dense joint is not formed, the strength of the joint is weak and causes gas / liquid leakage.

[0003] A joining method of welding a first article and a second article is used. In this case, there is a problem in that the heat affected zone becomes large, and a joining process having a complicated shape becomes difficult.

[0004] On the other hand, by utilizing the heat and mechanical action of ultrasonic waves, friction between the metals occurs, the adsorbed substances and the oxide film are destroyed, and relative movement occurs between the tool and the sample. A joining method of joining by rapid plastic flow is used. This method has characteristics such as the need for pressure and the joining of thin local portions, and is not suitable for joining having a large joining surface and a complicated shape.

Also, an ultrasonic soldering method is used in which an electronic component such as an electrode lead, an IC chip, and the like, and a mounting wiring board made of resin, glass, or the like are joined. In this method, bonding is performed by applying ultrasonic vibration that vibrates in parallel with the first and second objects to be bonded.

[0006] As described above, there are many methods and proposals for insert casting of ordinary metal (without applying ultrasonic waves). For ultrasonic bonding, solid-solid ultrasonic bonding and mounting and wiring of electronic parts are performed. Methods such as ultrasonic soldering have been used, but there have been few proposals for ultrasonic cast-in bonding methods. Prior art related to the present invention includes:
JP-A-2-258156, "Cast-in-casting method"
Conventional technology 1. ) And JP-A-3-213654 “intake manifold” (hereinafter referred to as Conventional Technique 2).

The prior art 1 relates to a method of ultrasonically casting a metal (including an alloy) between two metals (including alloys), wherein the first object is steel and the second object is high chromium cast iron as described in the embodiments. It is presumed that it is. Here, there is a description “pour the cast metal while applying ultrasonic vibration”.

[0008] In the prior art 2, as described in the embodiments, the present invention relates to an aluminum-aluminum cast-in method, in which an ultrasonic melting aluminum solder plating step is performed to enhance the joining property (diffusion bonding) in the subsequent cast-in joint. Like that.

In relation to the present invention (or the state of the art), any of the above-mentioned prior arts includes a timing of applying ultrasonic waves [including a solidification process (cooling curve) of a cast metal (molten metal). ] And bonding strength are not disclosed nor suggested. [The present invention will be described later. ]

[0010]

In recent years, it has become an important issue to join metal-based composite materials, ceramics or parts of ceramic-based composite materials to dissimilar materials such as metal castings. However, in this field, there is no proposal for a specific bonding method using ultrasonic waves.

Under these circumstances, there has been developed a method of performing effective bonding by inserting a solid-state metal or a metal-based composite material, a ceramic or a ceramic-based composite material into a molten metal casting and applying ultrasonic waves. Is expected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a small thermal effect, a large bonding strength, and an ultrasonic casting and bonding method capable of realizing more complex and dense bonding. It provides a joined body.

[0013]

SUMMARY OF THE INVENTION In order to solve the problems, the present invention provides a method in which a first object is placed in a mold, a second object is poured, and ultrasonic vibration is applied to the first object. An ultrasonic cast-in joining method for performing a continuous joining, wherein in the solidification process in which the second object is in a semi-molten state, the cast-in joint is performed while continuously or intermittently applying ultrasonic waves. It is a feature.

Here, the first article to be joined is a solid material selected from a metal (including an alloy), a metal-based composite material, a ceramic or a ceramic-based composite material.

[0015] Further, there is provided an ultrasonic cast-in joint obtained within a range not departing from the above-mentioned method, which is capable of joining between different kinds of materials and has improved joining strength. Note that this bonded body has a cavitation effect in the bonding process, and the first bonded object has been subjected to a cleaning process including removal of a surface oxide film.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention is directed to a joining method having the above-described structure, in which a first workpiece is placed in a mold, and a molten metal (second workpiece) is poured into the mold. In a solidification process of cooling from a molten (liquid) state to a semi-molten (solid-liquid coexistence) state, ultrasonic waves are continuously or intermittently applied to join the first and second workpieces. Is what you do.
Here, in the bonding process, the removal (cleaning treatment) of the surface oxide film of the first bonded object is included by the cavitation effect. In addition, it has been confirmed that the cavitation effect also contributes to the progress of a chemical reaction related to bonding.

In this case, as can be understood from the third aspect of the present invention, an ultrasonic wave is applied to the first workpiece and the angle of the ultrasonic vibration direction with respect to the surface of the first workpiece is set to 0. It can be in the range of up to 90 °.

The shapes and dimensions of the first object and the mold are not particularly limited, but preheating of the first object and the mold is required.

The bonding itself can be performed without limiting the angle between the ultrasonic vibration direction and the bonding surface as described above.
The above-mentioned limitation is set to a preferable range in that the influence of the angle on the bonding strength is recognized.

The frequency, output and application method of the ultrasonic wave are not particularly limited, but there are effects of the output and application method of the ultrasonic wave on the bonding strength. [Later description]

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is an explanatory view schematically showing the method of the present invention.

FIGS. 2, 3 and 4 are explanatory views showing an embodiment of the method of the present invention together with the apparatus configuration.

As can be seen from each figure, each device is provided with a mold (7) erected on the floor surface, and the mold (7) has a solid object (5, 8, 9). [First object] is inserted. The ultrasonic vibration is applied from the vibrating body (3) by the holding plate (4) or directly to the solid object (5, 8,
9). In each case, the intake manifold, which is a component of an automobile engine, is considered.

According to the above configuration, as shown in FIG. 2, a 6030 Al pipe [400 ° C.] preheated at another place is placed in a mold (7) heated by a built-in heater.

Then, the AC4C aluminum alloy [780 ° C.] (6) (hereinafter, AC4C; second work piece) melted elsewhere is poured into the mold (7), and is subjected to ultrasonic vibration (for example, 18 kHz).
z; 500 W) is applied to the metal pipe (5) by the holding plate (4). After the AC4C molten metal (6) has completely solidified, the vibrating body (3) is removed to complete the joining.

As shown in FIGS. 3 and 4, the joining is performed using a round bar (8) whose joining surface is perpendicular to the vibration direction and a round bar (8) whose joining surface is at an acute angle to the vibration direction. Carried out.

The joining strength of the joined body obtained by the method of the present invention will be described below based on experimental facts.

According to the ultrasonic cast-in bonding method of the present invention, 60
A test specimen of a joined body of 61Al pipe and AC4C was prepared.

Regarding the manufacturing conditions (manufacturing conditions), FIG.
Shows the cooling curve on the AC4C side near the bonding surface and the timing of applying ultrasonic waves, and FIG. 5B shows the shear strength of the manufactured bonded body test piece.

As can be seen from FIG. 5 (b), in the solidification process of cooling from the molten state to the semi-molten state, the shear strength related to joining is increased by continuously or intermittently applying ultrasonic waves. can do. That is, the shear strength is at least twice or more as compared with the case of the ultrasonic insert bonding in the liquid state.

Further, a test piece of a joined body of a steel pipe and AC4C was prepared.

FIG. 6 shows the relationship between the ultrasonic output and the shear strength of the test piece in this case. In this case, a shear strength of at least 50 to 100 MPa can be obtained with an ultrasonic output of 500 W.

Further, in the case of ultrasonic cast-in bonding to a round bar [first workpiece], bonding can be performed even when the bonding surface is at an acute angle in the ultrasonic vibration direction. [See Figs. 3 and 4]

Incidentally, the present invention is not limited to the above-described embodiment, and appropriate changes can be made without departing from the protection scope of the present invention. Examples of other possible embodiments include, for example, a solid object (5) [first object to be joined], a metal pipe, a round bar, a part having a complicated shape, a metal-based composite material, a ceramic or a ceramic-based composite material. It can be.

[0036]

The present invention has the above-described structure, and according to this, the joining property and the joining strength can be improved when casting a solid material (or a part) with a metal.

Moreover, the first object to be joined may be a solid material, and may have a component shape and a second object (cast metal).
It is industrially very useful because it does not matter if it is a different material.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing the method of the present invention.

FIG. 2 shows a metal pipe and an Al alloy (A) according to an embodiment of the present invention.
It is explanatory drawing which shows the ultrasonic cast-in joining method of C4C).

FIG. 3 shows a metal round bar (plane) according to another embodiment of the present invention.
FIG. 3 is an explanatory view showing a method of ultrasonically inserting and bonding an Al alloy (AC4C).

FIG. 4 shows a metal round bar (slope) according to another embodiment of the present invention;
FIG. 3 is an explanatory view showing a method of ultrasonically inserting and bonding an Al alloy (AC4C).

FIG. 5 is a view showing experimental facts on the joining strength of the joined body obtained by the method of the present invention, wherein (a) is a cooling curve (melt temperature) on the AC4C side near the joining surface and timing of applying ultrasonic waves. And (b) is a graph showing the shear strength of each of the manufactured joined body test pieces.

FIG. 6 is a graph showing the relationship between the shear strength and the ultrasonic output of the bonded body test piece in another experimental fact.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic oscillator 2 Ultrasonic vibrator 3 Vibration body 4 Holding plate 5 Metal pipe [Solid object; 1st object] 6 Molten metal [2nd object] 7 Mold 8 Metal round bar (flat) [Solid Object; first article to be joined] 9 Metal round bar (slope) [solid object; first article to be joined] X Ultrasonic cast-in joint (steel pipe / AC4C)

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Nobuyuki Fuyama 17-14 Tannamachi, Minami-ku, Hiroshima-shi, Hiroshima 2-302 Prefectural Government Building

Claims (5)

[Claims] 1. A stuffed cast member (hereinafter, referred to as a first workpiece) is placed in a mold, and a cast metal (hereinafter, referred to as a second workpiece) is poured to perform integral joining. In order to form a joined body, in an ultrasonic cast-in joining method in which ultrasonic vibration is applied to perform joining, in the solidification process in which the second object is in a semi-molten state, ultrasonic waves are continuously or intermittently formed. A method of performing an ultrasonic insert-molding, wherein the insert-molding is performed while applying pressure. 2. The ultrasonic insert bonding method according to claim 1, wherein the first object to be bonded is a solid material selected from a metal (including an alloy), a metal-based composite material, a ceramic, and a ceramic-based composite material. 3. An ultrasonic wave is applied to the first workpiece,
The angle of the ultrasonic vibration direction with respect to the surface of the first workpiece is set in a range of 0 to 90 °.
Ultrasonic cast-in bonding method as described. 4. The ultrasonic cast-in bonding method according to claim 1, wherein the ultrasonic wave is applied via a first workpiece, a second workpiece, or a mold. 5. A stuffed cast member (hereinafter, referred to as a first workpiece) is placed in a mold, a cast metal (hereinafter, referred to as a second workpiece) is poured, and ultrasonic vibration is applied. In the ultrasonic cast-in bonded body which is integrally joined while giving, a joined body obtained by continuously or intermittently applying ultrasonic waves in a solidification process in which the second object is in a semi-molten state. An ultrasonic cast-in joint having the following properties. (1) The first article to be bonded is a solid material selected from a metal (including an alloy), a metal-based composite material, a ceramic, or a ceramic-based composite material. (2) The bonding process has a cavitation effect, and the first object to be bonded is subjected to cleaning treatment including removal of a surface oxide film. (3) It has at least twice the shear strength as compared with the case of ultrasonic cast-in bonding in a liquid state.